1. Field of the Invention
The present invention relates to a lens-fitted photographic film unit with plural taking lenses, having different focal lengths for taking plural photographs simultaneously, more particularly, to a lens-fitted photographic film unit having an improved viewfinder.
2. Prior Art
There are well known lens-fitted photographic film units (hereinafter simply referred to as film units) having a preloaded photographic film and a simple photograph-taking mechanism, as disclosed in U.S. Pat. No. 4,884,087. When all the available frames of a photographic film have been exposed in such a film unit, it is necessary only to bring the film unit in its entirety to a photofinishing agent, without the need to remove the photographic film cassette from the film unit. Such film units have been used widely because of such ease and convenience.
In addition to ease and convenience, photographers recently have come to desire to take a wide-angle photograph with the main subject against a wide background and a telephotograph with the enlarged main subject in the same scene, for example when sightseeing, viewing children's school sports, or the like. In order to do this, it is possible to use a single-lens reflex camera with a zoom lens or a compact camera with a built-in zoom lens, or built-in telephotographic and wide angle lenses.
However, in this case, photographers need to take photographs of the same scene twice, by zooming or by selecting a telephotographic lens and then a wide angle lens. Therefore, when taking a moving main subject in e.g., school sports, this cannot be done, because it takes a certain time to switch between telephotography and standard photography.
In view of the above problem, there has been suggested a film unit with two taking lenses having different focal lengths, e.g., a telephotographic lens and a wide-angle (standard) lens by which a telephotographic sub-frame and a wide-angle (standard) sub-frame are simultaneously provided in a full size original frame of 135-type photographic film, upon depression of a shutter release button. Since the two taking lenses have different focal lengths, two viewfinders are also provided in the film unit to ascertain the taking fields respectively for telephotography and for wide-angle (standard) photography, or a field of view frame for telephotography is formed within a viewfinder for wide-angle (standard) photography.
However, it is impossible to form the film unit compactly because of the provision of the two viewfinders, even though miniaturization has been a recent trend. Also, when providing a plurality of taking lenses having different focal lengths, a shutter blade needs to be provided for each taking lens, and this requires a complex shutter mechanism, resulting in high manufacturing cost.